Halogens group 7

• Group 7


  The Halogens
• Group 7 elements


  • All are non-metals
  • Have 7 electrons in the outer shell
• Order down group 7

  • Fluorine
  • Chlorine
  • Bromine
  • Iodine
• Fluorine


  • Yellow gas at room temperature
• Chlorine


  • Pale yellow green gas at room temperature
• Bromine


  • Brownish red liquid at room temperature
• Iodine


  • Grey black solid at room temperature
• Moving down group 7

  1. Element becomes darker in colour

  2. Changes from gas to liquid to solid

  3. Elements lower in the group have higher melting points
• Group 7 elements


  Need to gain 1 extra electron to have a full outer shell and so form 1- ions
• As the number of shells of electrons increases down the group

  The outer electrons become further away from the positive nucleus
• Chlorine


  • Has the smallest number of shells
  • Outer electrons are closer to the positive nucleus
  • This makes the element more reactive as the ability to attract an electron is strongest